Many medical patients suffering from kidney disease are treated with a dialysis machine to cleanse their blood. A dialysis machine typically includes a blood pump and an extracorporeal blood circuit. Arterial blood is drawn from a patient's body, passes through the dialysis unit and dialyzed blood is returned to the patient's venous system. The extracorporeal blood circuit, which includes a length of extracorporeal blood circuit tubing several feet long at each end, may connect to the patient's arterial and venous systems directly via a large bore dialysis needle, or via separate dialysis access devices. The access devices each include a shorter tubular section, adapted at one end for connecting to an open end of the extracorporeal blood circuit tubing, and at the other end having a large bore dialysis needle for accessing the patient's arterial or venous blood.
Either or both of the extracorporeal blood circuit tubing and the access devices may include flow shut-off clamps and fluid access devices that have injection/administration port structures. The port structures provide mechanisms through which a dialysis administrator can, for example, safely access the arterial or venous blood flow to remove samples of the patient's blood or inject drugs or fluids. Some injection/administration ports are adapted for use with a needle syringe, while others are adapted to provide needleless syringe access with a Luer-type connection. The needleless access ports have a pressure-responsive structure or mechanism that opens the port upon pressure applied by a syringe tip.
It is desirable that the fluid access devices be safe and easy to use. It is also desirable that a fluid access device be low-cost, while still providing flexibility of use.